Anti-offset powder distributor and collector



March 8, 1955 w. T. DAN IELS ANTIOFFSET POWDER DISTRIBUTOR AND COLLECTOR2 Sheets-Sheet 1 Filed Aug. 22, 1951 Inventor h/MZ/AM 7.' DAN/15Attorney March 8, 1955 w. T. DANIELS 2,703,551

ANTIOFF'SET POWDER DISTRIBUTOR AND COLLECTOR Filed Aug. 22, 1951 2Sheets-Sheet 2 Inventor W/AL/AM TD/M/IELS A llorm'y United States PatentAN TI-OFFSET POWDER DISTRIBUTOR AND COLLECTOR William T. Daniels,Pittsburgh, Pa. Application August 22, 1951, Serial No. 243,117

Claims. (Cl. 118-308) This invention relates to an apparatus ofextremely simple construction capable of being mounted on or adjacent tothe frame portion of a printing press conveyor by which the freshlyprinted sheets are conveyed to a stacker or jogger for causing eachprinted sheet to pass through or beneath a fine film or screen of powderwhich coats the inked upper surface of the sheet to prevent the inktherefrom being oifset onto the bottom side of a superposed sheet of thestack.

More particularly, itis a primary object of the present invention toprovide an apparatus whereby a uniform film or screen of powder may bedischarged downwardly for uniformly coating the upper surfaces offreshly printed sheets passing therebeneath and wherein the amount ofpowder dispensed may be varied as required by extremely simple adjustingmeans.

Another object of the invention is to provide an apparatus which willeffectively prevent the accumulation of a powder cake within any part ofthe powder dispensing system and which would result in lumps of powderbeing from time to time dispensed onto a freshly printed sheet.

A further object of the invention is to provide an ap paratus wherebythe storage container for the powder will be constantly subjected to avibratory motion and also to a swirling air pressure creating awhirlwind action for breaking up small lumps which may occur in thepowder and for dispensing only the powder which is in a finely dividedform capable of travelling upwardly with the upwardly moving swirlingair.

Still a further object of the invention is to provide an apparatuswherein the powder storage container and the powder dispensing head willeach be constantly subjected to a vibratory and tapping action to retainthe powder constantly in motion and in suspension and to prevent it fromaccumulating or caking in either the container or the dispensing head.

Still a further object of the invention is to provide an apparatushaving collector means for collecting the powder not discharged onto theprinted sheets by a suction action and which powder would otherwise becarried in the air and blown onto other equipment including moving partsof the machinery, thus causing considerable damage. 1

Still a further object of the invention is to provide an apparatushaving a shield through which the screen of powder is dispensed ontoprinted sheets to prevent the powder from being blown by drafts of airaway from the sheeit during its downward travel from the dispensing heaVarious other objects and advantages of the invention will hereinafterbecome more fully apparent from the following description of thedrawings, illustrating a presently preferred embodiment thereof, andwherein:

Figure 1 is an end elevational view of the invention shown in an appliedposition;

Figure 2 is a side elevational view, partly in vertical section thereof,taken substantially along a plane as indicated by the line 2-2 of Figure1;

Figure 3 is a cross sectional view of the apparatus taken substantiallyalong a plane as indicated by the line 3-3 of Figure 2;

Figure 4 is an enlarged fragmentary longitudinal sectional view, partlyinside elevation, of a portion of the apparatus;

Figure 5 is a horizontal sectional view taken substan- 2,703,551Patented Mar. 8, 1955 ice tiallX along a plane as indicated by the line5--5 of Figure Figure 6 is an enlarged cross sectional view takensubstantially along a plane as indicated by the line 6-6 of Figure 4,and

Figure 7 is an enlarged cross sectional view, similar to Figure 3 of thecollector portion of the apparatus.

Referring more specifically to the drawings, the antioifset powderdistributor and collector in its entirety is designated generally 8 andincludes a supporting bracket, designated generally 9 having a portion10 which is adapted to be secured by fastenings 11 to a side rail 12 ofa frame of a printing press conveyor 13 by means of which freshlyprinted sheets 14 are conveyed in a conventional manner from theprinting press to a jogger or stacker 15. The bracket 9 is also providedwith a bottom portion defining a downwardly opening socket 16 to receivethe upper end of a standard 17 of a pedestal 18 which is intended torest on a floor surface and by means of which the bracket 9 may besupported, in lieu of being secured to the conveyor rail 12. The bracket9 is also provided with an upwardly extending upper end portion 19 whichis disposed outwardly of the rail 12 and which extends upwardly withrespect to the bracket portion 10. The portion 19 is provided on itsouter side with an outwardly projecting mounting flange 20 which isdisposed substantially in a vertical plane and which provides a supportfor an electric motor 21 which is mounted on one side thereof and a pump22, which is mounted on the opposite side of the flange 20. One end ofan armature shaft 23 of the motor 21 may extend through and bejournalled in the flange 20 and forms the drive shaft of the pump 22.The opposite end of the armature shaft 23 projects from the opposite endof the motor 21 into the casing of a blower 24 to form the blower driveshaft. The blower 24 is mounted beyond said last mentioned end of themotor 21 and is supported thereon by suitable supporting elements 25.

As best seen in Figure 4, a screw fastening 26 extends outwardly throughthe bracket portion 19 above the flange 20, through the lower portion ofa resilient plate 27 and is threaded into the shorter leg 28 of anL-shaped supporting arm 29, the terminal of which leg abuts the plate 27so that the lower portion of said plate is clamped between said leg andthe upper end of the bracket portion 19. The other, outwardly offsetupwardly extending leg 30 of the supporting arm 29 supports anelectromagnet, designated generally 31, on the upper end thereof andwhich is secured thereto by a fastening 32 which additionally supports aswitch, designated generally 33, having a stationary contact 34 and amovable contact 35 which is normally spring biased into a circuitclosing position in engagement with the contact 34. The switch 33 isinterposed in a conductor 36 which supplies current to the coil 37 ofthe electromagnet 31 for magnetizing the core 38 thereof. The electriccircuit of the electromagnet also includes a negative or ground wire orconductor 39.

The resilient plate 27 extends upwardly from its secured lower end toabove the electromagnet 31 and has a portion thereof disposed beyond theouter right hand end of the core 38 and which would normally be disposedin contact therewith when an adjusting screw 40 is retracted. Theadjusting screw 40 is threaded through the upright arm portion 30 andextends inwardly therefrom to abut against the plate 27 and is advancedfor tensioning the plate 27 and swinging it away from the core 38. Astem 41, preferably formed of an electrical insulating material, has oneend secured to the movable contact 35 and projects therefrom toward theupper end of the plate 27 and has its opposite end disposed to beengaged by the plate 27 when the latter is disposed adjacent to the core38, for a purpose which will hereinafter be described.

An internally threaded boss 42 is secured to the opposite side of theplate 27, to the side thereof disposed adjacent the core 38, and ispreferably disposed below the level of the core 38, as seen in Figure 4.A tube 43 has an externally threaded end 44 threaded into the boss 42and by means of which said end is closed and the tube 43 is supported onthe plate 27 in substantially a horizontal plane substantiallyperpendicular to the plane of the plate 27. The tube 43 is provided witha restricted internally threaded opposite end 45 and is additionallyprovided with a partition wall 46 adjacent said end 45 completelyclosing off direct communication between the ends 44 and 45. The tube 43has an internally threaded cap 47 secured to the bottom portion thereofbeneath the partition 46 to threadedly receive the neck of a transparentcontainer 48 such as a glass jar. The partition 46 forms a relativelylong chamber 49 within the tube 43 between said partition and its end 44and a smaller chamber 50 between the partition 46 and said restrictedend 45. A tube 51 has one end mounted in a boss 52 and communicates withthe chamber 49 and extends downwardly into the container 48 and has acurved lower discharge end 52, as best seen in Figure 5, which is curvedclockwise as viewed from above and which has its lower discharge endopening substantially horizontally and adjacent a portion of thecylindrical side wall of the jar 48, preferably at a level of about twoinches above the bottom of said container 48. A short tube 53 is mountedin a boss 54 of the tube 43 and has an upper end opening into thechamber 50 and a lower end opening into the upper portion of thecontainer 48.

A conduit 55 leads from the outlet of the pump 22 and has an outlet endwhich is secured to the tube 43, between its end 44 and the cap 47 andwhich opens into the chamber 49, said conduit 55 preferably including aflexible portion 56. The tube 43 is provided with an air release port oropening 57 which communicates with the chamber 49 between the conduit 55and its end 44.

A collar 58 is turnably mounted on the tube 43 and has acircumferentially elongated tapered opening 59 which is movable into andout of registry with the port 57 for closing, opening or partiallyopening said port whereby a portion of the air entering the chamber 49from the pump 22 may be released through the port 57 to maintain anydesired pressure in the tube 51. The collar 58 has sufficient frictionalengagement around the tube 43 to maintain any position to which it isadjusted.

A discharge manifold, designated generally 60, comprises an elongatedconduit or pipe having a closed outer end 61 and an externally threadedinner end 62 which threadedly engages the restricted end 45 so that thebore of the pipe 60 is in communication with the chamber 50. The pipe 60is of a length to extend transversely across the conveyor 13 and isdisposed thereabove and provided in its underside with a plurality oflongitudinally spaced discharge ports 63. A plurality of split rings orcollars 64 are turnably mounted on the pipe 60 for frictional engagementtherewith and are slidable longitudinally thereof so that said rings,forming valves, may be disposed over certain selected ports 63 forshutting off said ports and so that the powder dispensed from the pipe60 will then be concentrated in particular areas located beneath theother, exposed discharge ports 63.

A resilient strip 65, possessing a greater degree of resiliency than theplate 27, has one end secured to the plate 27 above the boss 42, as byfastenings 66, and extends outwardly from the outer side of said plateand substantially perpendicular thereto and is disposed over the tube43. A weighted block 67 is secured by one or more fastenings 68 to thestrip 65 and depends from the free end thereof and has its lower endnormally disposed in engagement with a plate 69 which is secured to theupper surface of the free end of the tube 43 and which provides asubstantially fiat top surface to be engaged by the block 67.

A powder trap or collector, designated generally 70, includes an opentop receptacle which is disposed beneath and extends transversely acrossthe conveyor 13. Said receptacle 70 has end walls 71 which are securedby brackets 72 and fastenings 73 to the side rails 12 and 12a of theconveyor 13. The receptacle 70 is relatively shallow except for adeepened portion or well 74 which extends from end-to-end thereof and isdisposed adjacent one longitudinal side of said receptacle. A tray 75 isremovably mounted in the bottom of the well 74 and is removabletherefrom through an opening afforded in one end wall 71 by a removablesection 76 thereof which is retained in a closed position by a fasteningor fastenings 77, as best seen in Figure 2. An elongated, downwardlyopening hood 78 of substantially U-shaped cross section extends thelength of and is disposed within the well 74 with its open lower endabove and adjacent the top of the tray 75 and is secured at its ends tothe end walls 71. An upper strip of mesh wire fabric 79 is secured to apair of angle members 80 and is supported thereby intermediate of thetop and bottom of the hood 78 and extends from end-to-end thereof, saidmembers 80 being secured to the side walls of the hood. A bottom stripof mesh wire fabric 81 is similarly secured to a second pair of anglemembers 82 and likewise extends from end-toend of the hood 78 below andspaced from the strip 79. The angle members 82 are demountably supportedadjacent the open bottom of the hood 78 by a plurality of pins orsupporting rods 83 which extend therethrough and through the side wallsof the hood. The chamber within the hood 78 between the mesh wire fabricstrips 79 and 81 is filled with a mass of cotton or similar loosematerial 84 which is pervious to air. A conduit 85 has one end extendingthrough one end wall 71 and which opens into the upper portion of thehood 78 above the mesh wire fabric strip 79. The opposite end of theconduit 85 is connected to the intake of the blower 24.

The end walls 71 are provided with upwardly projecting extensions 86which extend upwardly from the trap receptacle 70 on the inner side ofand adjacent the side rails 12 and 12a and which are secured at theirupper ends to end walls 87 of a shield, designated generally 88. Theshield 88 has upwardly converging side walls 89 the upper, adjacentlydisposed edges of which are laterally spaced from one another anddisposed above the upper edges of the end walls 87 to define an openupper portion 90 of the shield 88 in which the portion of the dischargemanifold 60, having the discharge ports 63, is disposed. The enlargedopen lower end 91 of the shield 88, as defined by the bottom edges ofthe end walls 87 and side walls 89, is disposed above and adjacent theupper surface of the conveyor 13 so that the sheets of paper 14travelling thereon may pass beneath the open bottom of the shield 88. Asseen in Figure 2, the length of the shield 88 is greater than the widthof the printed sheets 14 so that all portions of the sheets will passbeneath the open bottom of the shield. Likewise, as seen in Figure 3,the open top of the trap receptacle 70 is larger than the open bottom 91of the shield, which is disposed directly thereabove, so that all powderdischarged from the bottom of the shield 88 when a sheet of paper 14 isnot disposed therebeneath, will be discharged into the trap receptacle70. The receptacle extensions 86 may be secured by fastenings 92 to theshield walls 87 for detaching the shield from the trap while the partsare removed from or applied to the press conveyor 13.

To use the anti-offset powder distributor and collector 8, the container48 is filled with anti-offset powder P to a level below that of theoutlet end 52 of the tube 51 and the screw 40 is adjusted so that theplate 27 is displaced away from the core 38 and out of engagement withthe stem 41 to permit the contact 35 to engage the contact 34. Assumingthat direct current is being used, the current will flow through thecircuit including the closed switch 33 to energize the coil 37 tomagnetize the core 38 which will attract the plate 27 and cause it toswing from right to left of Figure 4 from its dotted line to its fullline position thereby causing the tube 43 and discharge manifold 60 toswing upwardly. As the upper end of the plate 27 swings to its full lineposition of Figure 2 it will strike the stem 41 to thereby displace thestem 41 and movable contact 35 from right to left to disengage thecontact 35 from the contact 34 thus opening the switch 33 to de-energizethe coil 37 and de-magnetize the core 38. The plate 27 will then bereleased and will be spring biased back to its dotted line position ofFigure 4 by the pressure exerted thereon by the screw 40 to swing thetube 43 and discharge manifold 60 downwardly, thus completing avibration of these parts with the plate. Each time that the plate 27swings away from the core 38 it will disengage the stem 41 to permit theswitch 33 to resume a closed position for again energizing the coil 37,and it will thus be apparent that the number of vibrations of the plate27 in a given period of time may be varied by adjusting the screw 40.

If alternating current is used the switch 33 is omitted and the plate 27will be vibrated a number of times per second corresponding to thenumber of cycles of the alternating current. Likewise, the vibration ofthe plate 27 by either a direct or alternating current will cause a moreviolent but less rapid vibration of the more resilient strip 65 and as aresult thereof the weighted block 67 will be swung into and out ofengagement with the plate 69 for producing a sharp tapping of the plateand additional agitation or vibration of the tube 43 and manifold 60 andlikewise of the container 48 which will effectively prevent the offsetpowder P, from caking in the bore of the manifold 60 or in the chamber50 and which will likewise keep the powder within the container 48 in aconstantly agitated condition and in motion. Whenever the apparatus isin operation to produce the vibration and agitation as previouslydescribed, the motor 21 is likewise in operation for driving the pump 22and blower 24. Accordingly, air will be drawn inwardly through theintake, not shown, of the pump 22, and expelled through the conduit 55and chamber 49 into the tube 51 from which the air is discharged throughthe tube outlet 52 in a clockwise direction as viewed from above. Theamount of air discharged into the container 48 and the pressure of theair therein may be varied to a great degree and within a wide range byadjusting the valve 58, 59 from a position completely closing the port57 to a position in which the port 57 is fully exposed and in whichlatter position an extremely low pressure will exist in the container48. By regulation of the valve 58, 59 a quantity of offset powder whichwould last for approximately twenty-four hours operation with the port57 fully opened can be dispensed in a few minutes with the port 57completely closed, so that a very accurate control of the amount ofoifset powder dispensed, depending upon the amount of ink applied to thesheets 14 passing under the apparatus 8, may be efiiciently accomplishedby means of the valve 58, 59.

As uniformity in the rate of discharge of the offset powder is ofcritical importance to the efliciency of a distributing apparatus, thearrangement of the tube 51 and the means for rapidly vibrating andagitating the tube 43, manifold 60 and container 48 is of extremeimportance.' The vibration and agitation of the container 48 tend tocause the moving powder to pile slightly toward the left side of thecontainer as seen in Figure 4 and any lumps existing therein will workupwardly therethrough and will then roll downwardly to the right-handfar side of the container and repeat this operation which will graduallygrind the lumps into powder of intended fineness. Similarly, the outletend 52 of the tube 51 will be vibrated so that the air dischargedtherefrom will not be concentrated entirely in one portion of thepowder. The agitation of the powder will prevent the air from forming ahole or cavity therein which tends to cause caking, subsequent wallcollapsing and resulting intermittent feeding of large quantities ofpowder. Actually, very little of the air is blown against the powder butrather the air is expelled circularly around the container above thepowder creating a whirlwind efiect whereby the loosened powder is pickedup by the air rising through the center of this minute whirlwind andcarried with this air through the tube 53, chamber 50 and along themanifold 60 to be discharged uniformly through all of the exposeddischarge ports 63. Any lumps picked up by the swirling air due to theiradditional weight will be thrown centrifugally against the wall of thecontainer 48 and in this manner the lumps will be broken up until theyassume sufiicient fineness to be carried upwardly with the rising airstream into the manifold 60. The constant vibration and tapping of thetube 43 and manifold 60 will prevent any of the powder passing throughsaid manifold and the chamber 50 from accumulating therein so that anydanger of the powder caking and subsequently being discharged in a largequantity is completely avoided. As previously stated, certain of theoutlet ports 63 can be selectively closed so that discharge of thepowder will be concentrated above the area of sheets containing thepreponderance of the ink.

It will also be readily apparent that the screen of powder and air beingconstantly discharged downwardly from the exposed ports 63 will beprevented by the shield 88 from being blown in any direction by draftsso that a substantially uniform screen of powder will be spread over thearea of each sheet 14 as it passes under the exposed ports 63. Muchdifficulty and damage is caused by powder escaping from a distributingapparatus and which will be overcome to a considerable extent by theshield 88. However, a part of the escaped powder results from the factthat powder is discharged through the gaps between the sheets 14 beingconveyed over the conveyor 13; however, applicants apparatus includesthe collector 70 which will effectively catch all powder passingdownwardly through the conveyor 13 between the sheets 14 travellingthereover. This is accomplished since the shield 88 discharges directlyover the larger open top of the collector trap 70 and additionallybecause the blower 24 creates a suction through the conduit in the topof the hood 78 so that a suction constantly exists in the trapreceptacle 70 while the powder is being dispensed and which effectivelytends to draw all of the powder not applied to the sheets 14 into thetrap 70 and downwardly into its well 74 to be caught in the pan or tray75. 'lhe pervious material 84 is provided as a filter and also functionsto insure that a substantially uniform suction or vacuum will exist fromend-to-end of the hood 78 so that the powder laden air will be drawninto the trap from all portions of the shield 88 and collected in thetray 75.

It will be readily apparent that the blower 24 could be omitted and theconduit 85 then connected to the inlet of the pump 22 or said pump couldbe omitted and the conduit 55 could then be connected to the outlet 93of the blower 24. However, all types of pumps and blowers may not beemployed as the pump 22 only supplies air at a very low pressure, of theorder of a few ounces, to the container 48. Due to this slight airpressure and the fact that air is not stored, practically nocondensation occurs thereby eliminating a problem which causes muchtrouble in other apparatuses of a similar character where a storage tankhaving a relatively high pressure is employed and some type of condenseror air filter must be utilized to remove the moisture. This likewiseenables the apparatus 8 to be much lighter in weight and to occupyconsiderably less space. J

Various modifications and changes are contemplated and may obviously beresorted to, without departing from the spirit or scope of the inventionas hereinafter defined by the appended claims.

I claim as my invention:

1. An anti-offset powder distributing apparatus comprising a stationarysupporting structure, an elongated discharge manifold adapted to extendacross a printing press conveyor having a plurality of downwardlyopening dis charge ports, a resilient member secured to said supportingstructure and supporting said discharge manifold, means vibrating saidresilient member for imparting a vibratory motion to the dischargemanifold, a storage container for an offset powder having an outletadjacent its top communicating with said discharge manifold, and an airpressure supply means having an outlet opening within and adjacent thebottom of said container for picking up and conveying offset powder withthe air through the container outlet, along the discharge manifold andoutwardly through the discharge ports thereof to form a descendingscreen of powder for application to freshly printed sheets beingconveyed along said conveyor beneath the discharge manifold, a tubularmember connecting the manifold and resilient member, said storagecontainer being supported by the tubular member to vibrate with saidresilient member and discharge manifold for agitating the offset powdercontained therein, the discharge end of said air pressure supply meansbeing disposed to discharge the air into the storage containersubstantially horizontally and circumferentially thereof and above thelevel of the offset powder for causing the powder to be further agitatedto break up any lumps therein and for lifting powder which is in afinely divided form by a whirlwind action through the outlet in the topof said storage container.

2. An anti-offset powder distributing apparatus comprising a stationarysupporting structure, an elongated discharge manifold adapted to extendacross a printing press conveyor having a plurality of downwardlyopening discharge ports, a resilient member secured to said supportingstructure and supporting said discharge manifold, means vibrating saidresilient member for imparting a vibratory motion to the dischargemanifold, a storage container for an offset powder having an outletadjacent its top communicating with said discharge manifold, and an airpressure supply means having an outlet opening within and adjacent thebottom of said container for picking up and conveying offset powder withthe air through the container outlet, along the discharge manifold andoutwardly through the discharge ports thereof to form a descendingscreen of powder for application to freshly printed sheets beingconveyed along said conveyor beneath the discharge manifold, saidresilient member comprising an upstanding resilient plate secured at itslower end to said supporting structure, a rigid tubular member havingone end secured to and closed by said resilient plate and having itsopposite end connected to an end of said discharge manifold forconnecting the discharge manifold and resilient plate, a partition walldividing said tubular member into conduit portions one of which forms apart of said air pressure supply means and the other of which forms apart of said storage container outlet.

3. A distributing apparatus as in claim 2, a spring secured to andprojecting perpendicularly from said resilient plate and disposed abovesaid tubular member, a weighted block secured to and depending from thefree end of said spring having a lower end disposed above and normallyin contact with said tubular member and forming a tapper, said tapperbeing oscillated by the vibration of the spring with and relatively tothe resilient plate for tapping the tubular member to additionallyvibrate said tubular member, discharge manifold and storage container,said spring possessing a greater degree of resiliency than the resilientplate.

4. An anti-offset powder distributing apparatus comprising a dischargemanifold adapted to extend across a printing press delivery and having aplurality of downwardly opening discharge ports for discharging anofiset powder downwardly onto freshly printed sheets conveyed by saiddelivery beneath the discharge manifold, means supporting said dischargemanifold, a storage container for ofiset powder supported by saidsupporting means having an outlet communicating with the dischargemanifold, agitating means including means for vibrating a portion ofsaid supporting means for imparting a vibratory motion to the dischargemanifold and storage container, an air supply means supplying air underpressure to said storage container and having a discharge end openinginto the storage container above and adjacent the level of the powdercontained therein, and a stationary shield having an enlarged openbottom adapted to be disposed above and adjacent the printed sheetspassing beneath the discharge manifold, said shield having a restrictedupper end in which said discharge manifold is loosely disposed forvibration relatively to the shield.

5. An anti-offset powder distributing apparatus comprising a dischargemanifold adapted to extend across a printing press delivery and having aplurality of downwardly opening discharge ports for discharging anoffset powder downwardly onto freshly printed sheets conveyed by saiddelivery beneath the discharge manifold, means supporting said dischargemanifold, a storage container for offset powder supported by saidsupporting means having an outlet communicating with the dischargemanifold, agitating means including means for vibrating a portion ofsaid supporting means for imparting a vibratory motion to the dischargemanifold and storage container, an air supply means supplying air underpressure to said storage container and having a discharge end openinginto the storage container above and adjacent the level of the powdercontained therein, and a tapper unit supported by the vibrating part ofsaid supporting means for vibrating movement therewith and relativelythereto and having a tapper element for striking a part of saidvibrating portion of the supporting means for additionally vibrating andagitating the discharge manifold and storage container.

References Cited in the file of this patent UNITED STATES PATENTS1,659,179 Wilson Feb. 14, 1928 2,112,759 Boyer Mar. 29, 1938 2,151,737Bryan Mar. 28, 1939 2,261,212 Beregh Nov. 4, 1941 2,266,849 Cole Dec.23, 1941 2,303,458 Hermann et al Dec. 1, 1942 2,375,766 Britcher May 15,1945 2,467,097 Rooney Apr. 12, 1949

